Skunk2 Cold Air Intake MAF scaling

[KoolBRZ]

I got the new Skunk2 Cold Air Intake because I wanted performance, I'm on the ESC list, and I don't want to connect it to the stock airbox. The elbow is removable so should connect right up to the ESC with the right adapter. Problem is, the intake comes with an insert to bring the size down to about OEM size, but the MAF scaling isn't anywhere close. I've been looking at LTFT's in the 20's and 30's, so I've been learning how to scale a MAF. I'm attaching a spreadsheet of my most successful MAF scale for those of you who have the Skunk2 CAI. I gotta say, I didn't think MAF scaling would make much of a difference, but I love the way my car's running now. MPG is better too, at least when I can keep my foot out of it. But, it's just so fun...you know.

https://drive.google.com/file/d/0B4W...ew?usp=sharing

If you want the spreadsheet itself, just PM me with an email address to send it

[joshbohmer]

Thought I would add my efforts with the Skunk2 intake in case anyone else finds it useful. I wanted to have the OEM insert removed so I set about putting this together.

Because of the huge difference (+~70%) between this configuration and the stock calibration i've rescaled the table from 0.9V->5V to 0.9V->4V because you hit the 200g/s max well before 4V now.

As always, use this ONLY as a place to start. When I removed the insert my trims were so high (+50%) I ended up just guessing where to start just so I felt comfortable driving the car to collect the data I needed for a proper calibration.

This scale keeps me between +-3% STFT & LTFT. So hopefully you find it useful to get you going.

[KoolBRZ]

Originally Posted by joshbohmer

Thought I would add my efforts with the Skunk2 intake in case anyone else finds it useful. I wanted to have the OEM insert removed so I set about putting this together.

Because of the huge difference (+~70%) between this configuration and the stock calibration i've rescaled the table from 0.9V->5V to 0.9V->4V because you hit the 200g/s max well before 4V now.

As always, use this ONLY as a place to start. When I removed the insert my trims were so high (+50%) I ended up just guessing where to start just so I felt comfortable driving the car to collect the data I needed for a proper calibration.

This scale keeps me between +-3% STFT & LTFT. So hopefully you find it useful to get you going.

I tried your scale, but it didn't work in open loop, so I took some guesses and used maf scaling master 1.63 to get the closed loop portion close, then I logged some WOT runs to get the scale I have now. Attached is the PDF of the spreadsheet I made of the MAF scale.

[joshbohmer]

Originally Posted by KoolBRZ

I tried your scale, but it didn't work in open loop, so I took some guesses and used maf scaling master 1.63 to get the closed loop portion close, then I logged some WOT runs to get the scale I have now. Attached is the PDF of the spreadsheet I made of the MAF scale.

Interesting. Did you update the input voltage line as well as the g/s line? You'll notice above 2.5V it's very different. 2.5V is roughly where you'll switch over to OL, and if it wasn't updated accordingly would throw off the scale by a huge amount.

[KoolBRZ]

Originally Posted by joshbohmer

Interesting. Did you update the input voltage line as well as the g/s line? You'll notice above 2.5V it's very different. 2.5V is roughly where you'll switch over to OL, and if it wasn't updated accordingly would throw off the scale by a huge amount.

All my tools work with .89-5v range, and I'm not about to change all my tools, so I re-scaled your 4v scale to 5v to work with my tools.

Here's the current scale I'm working on. It's not perfect, since I have a small exhaust leak, but once I get that fixed the final tweaks should get it right on.

[Hyper4mance2k]

Old carburetor guy question incoming: how are you guys adjusting the MAF scale?

[steve99]

Originally Posted by Hyper4mance2k

Old carburetor guy question incoming: how are you guys adjusting the MAF scale?

MAF Scaling see here http://www.ft86club.com/forums/showthread.php?t=64790

if you interested read the other stuff below.

[EffaressNOOB]

Originally Posted by KoolBRZ

I got the new Skunk2 Cold Air Intake because I wanted performance, I'm on the ESC list, and I don't want to connect it to the stock airbox. The elbow is removable so should connect right up to the ESC with the right adapter. Problem is, the intake comes with an insert to bring the size down to about OEM size, but the MAF scaling isn't anywhere close. I've been looking at LTFT's in the 20's and 30's, so I've been learning how to scale a MAF. I'm attaching a spreadsheet of my most successful MAF scale for those of you who have the Skunk2 CAI. I gotta say, I didn't think MAF scaling would make much of a difference, but I love the way my car's running now. MPG is better too, at least when I can keep my foot out of it. But, it's just so fun...you know.

https://drive.google.com/file/d/0B4W...ew?usp=sharing

If you want the spreadsheet itself, just PM me with an email address to send it

Hey buddy, me again!

Is this original post and your MAF Scale "WITH" the insert? I hav the Skunk 2 installed running Stage 2 UEL E85 and my LTFT is right under 20%

[KoolBRZ]

I took my Skunk2 off to install the Phantom supercharger because it uses the stock airbox for support. I'm going to weld up a support for it though and reinstall the Skunk2. I'll have the MAF scale without insert all figured out then. I would have had it all figured out already if it hadn't been for that Port Injection responding erratically. It can't respond as fast as Direct Injection, so there is inevitable overcompensation to quick throttle adjustments. At high rpms the difference is imperceptible, but at low rpms it is easily noticeable in the logs.